- See odds as a price. Odds are the price of a bet. A -110 total means you pay a 10 percent premium to win 100, and that premium is how the book profits.
- Find the implied probability. Convert each side's odds to a probability. If both sides sum to 105 percent, the extra 5 percent is the vig you must overcome.
- Strip the vig for the fair price. A no-vig calculator removes the margin to show the true fair odds, which is your benchmark for whether a price is good.
- Take the best available number. Because every book prices differently, the highest plus or lowest minus you can find is a direct, repeatable edge.
How the vig works
On a two-way market priced -110 / -110, both sides' implied probabilities add to about 105 percent, not 100. That extra 5 percent is the vig. Bet 110 to win 100 on each side and the book keeps the difference regardless of who wins. Over thousands of bets, that margin is the house edge you are fighting, which is why the price you take matters as much as the pick.
Why line shopping beats the vig
If one book has your side at -110 and another at -105, taking -105 lowers the vig you pay on every bet. Do that consistently and you claw back a chunk of the house edge without handicapping a single game. That is why sharp bettors hold accounts at several books and always shop the line.
Frequently asked questions
What is the vig?
The vig, or juice, is the margin a sportsbook builds into its odds. It is why the implied probabilities of both sides of a bet add up to more than 100 percent.
Do odds show the real probability of an outcome?
No. Odds show the book's shaded probability, inflated by the vig. Strip the vig with a no-vig calculator to see the fair price.
Keep going
21+. For entertainment and educational purposes, not financial advice. If gambling stops being fun, take a break. 1-800-GAMBLER. Regulated US books only.